Accurate analysis of fluids is important to many industries. By way of example, in the provision and propagation of drinking water, it is considered important to obtain accurate measurements of different parameters such as alkalinity and/or turbidity, as sensed or sampled at different locations. Some such locations can involve different points along a natural watercourse that feeds into a water supply, while other such locations can involve different points in the (post-treatment and filtration) propagation network of the water supply itself. Alkalinity is a required reporting parameter for many regulatory agencies such as the Environmental Protection Agency (EPA) and the Food and Drug Administration (FDA); the EPA has listed pH as a secondary drinking water regulation. Turbidity is a measure of the cloudiness or haziness of a fluid (e.g., that may be contributed to be individual particles) and thus is considered to provide a reliable measurement of water quality. Turbidity is measured in nephelometric turbidity units (NTUs), and different regulatory standards may apply for quantitative measures of NTUs at different points of a water supply network (which, again, could include one or more watercourses that feed into a water supply, or different points in a propagation network, alike).
To measure one or more parameters related to water quality at different points of a water supply network, sensors may be placed to obtain direct measurements. Thus, for instance, Secchi disks or turbidity tubes may be used to measure turbidity in watercourses or reservoirs, or even in points of a water propagation network. Measurements from these can be electronically transmitted to a data logger (which, for instance, can accept data from five to ten sensors), via a wired or wireless connection. However, reliability of the sensors may need to be ensured via an additional check of water samples at another measuring device. Such a measuring device may be disposed in a fixed or mobile laboratory, or can be portable to take measurements at or near the location of a sensor. When conducting such an additional check, a comparison can be made with one or more measurements from a sensor (e.g., itself taken at the same time that a water sample is collected for the additional check) and, if necessary, the sensor can be recalibrated based on the comparison.
Typically, a significant number of sensors at different points of a water supply network may need to be regularly checked and, if necessary, recalibrated. To accomplish this, it is typically the case that numerous water samples are collected in containers at the locations of such sensors, preferably at times coincident with one or more measurements being triggered and taken by a sensor. The containers are typically labeled by hand or via pre-printing, showing a visual/verbal indication of identifying information such as the location from which the sample is taken. However, there is typically nothing else to ensure that the sample in a container is clearly associated with a particular sensor and/or location. Simple human error may thus result in incorrect associations being made (between containers and sensors/locations), with the consequence of incorrect or misleading data (e.g., obtained at a laboratory) for sensor recalibration.